need help with s13 hesitating

[William_s13]

hi i have a 1990 s13 hatch with a manual s14 ka24de. recently it has been giving me a few problems at first i had a bad ecu so i swapped it out for an s13 auto ecu, and now as soon as i get to about 4000 rpm it just stops climbing revs down and then catches itself over and over unless i let off. ive replaced spark plugs,wires, fuel filter, ecu, swapped maf, checked timing, changed coil, new oem fuel pump from advanced auto so it might be that i just wanted to see if anyone else knew anything to try. also recently everytime it hesitates the rpm gauge starts freaking out and jumping around. only codes i have on the ecu are 14 and 54 which i know my speed sensor it bad but im not sure about the other please help me out or point me in the right direction if i missed a thread i have been searching all day and need an answer because i have work in the morning

[Ka-t in progress]

Sounds like it may be in limp mode,should throw a check engine light for it though.

[William_s13]

the cel is on and its for the speed sensor. would that cause it to go into limp mode?

[Ka-t in progress]

Will it rev over 4k in neutral? U also may want to use a voltmeter and test your tps.

[William_s13]

yeah it revs up smoothly in neutral way past 4k and the tach even works fine un neutral but once i start moving the tach jumps around and it wont rev past 4k and i tested my tps multiple times because i put it in a few months ago

[Ka-t in progress]

I'm not to sure at this point. If I had to guess its something to do with the ecu,did it happen before you changed the ecu? Only other thing that comes to mind is the cam sensor.

[William_s13]

the ecu i had before made it run horrible all the time and it woundnt even throw codes even if i unplugged anything and it worked perfect when i first put the ecu in. is the cam sensor in the distributor?